Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
1.
Dev Genes Evol ; 208(5): 274-82, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9683743

RESUMO

The Drosophila gene shuttle craft (stc) is expressed zygotically in the embryonic central nervous system (CNS) where it is required to maintain the proper morphology of motoneuronal axon nerve routes following their migration from the ventral cord. Here, we report that a prominent maternal source of STC protein is also present throughout both oogenesis and embryogenesis. To determine whether this maternal component is required in the ovary and/or embryo, we used the Drosophila autosomal dominant female sterile technique to generate germ-line clones that lacked the stc maternal function. Our results demonstrate that a maternally derived source of STC protein is required during embryogenesis but not oogenesis. In contrast to the zygotic phenotype, the primary defect in embryos derived from stc germ-line clones affects segmentation by causing disruptions and deletions in distinct thoracic (T1-T3) and abdominal (A4-A8) segments. These localized defects are responsible for additional phenotypes observed later in development which include gaps in the ventral nerve cord and deletions of denticle belts in the cuticle. An additional phenotype occurring in all other neuromeric segments consists of the misguided migration of motoneuronal axons as they project out of the ventral nerve cord. Thus, the stc zygotic function is required later in development and cannot correct the segmentation and subsequent CNS abnormalities associated with loss of its earlier acting maternally derived activity.


Assuntos
Drosophila/embriologia , Genes Letais/genética , Fatores de Transcrição/fisiologia , Animais , Sistema Nervoso Central/fisiologia , Células Clonais/metabolismo , Proteínas de Ligação a DNA/fisiologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Genes de Insetos/genética , Células Germinativas/fisiologia , Imuno-Histoquímica , Hibridização In Situ , Proteínas de Insetos/fisiologia , Morfogênese/fisiologia , Oócitos/metabolismo , Fenótipo
2.
J Urol ; 159(4): 1247-50, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9507846

RESUMO

PURPOSE: Since most patients do not undergo repeat sextant prostate biopsies after a biopsy is positive for prostate cancer, the true incidence of false-negative biopsies is not well defined. We assess the incidence and clinical significance of false-negative sextant prostate biopsies in patients undergoing radical prostatectomy. MATERIALS AND METHODS: A total of 118 patients with biopsy proved prostate cancer underwent repeat sextant prostate biopsy before enrollment in a prospective randomized trial of radical prostatectomy with or without neoadjuvant hormonal therapy. Clinical parameters were assessed to determine potential sources of bias. Pathological parameters and prostate specific antigen relapse-free survival rates were compared to determine the clinical significance of false-negative biopsies. RESULTS: Of the 118 patients 27 (23%) had a negative repeat sextant biopsy. Except for initial clinical stage, no differences were noted in the clinical or pathological parameters, or prostate specific antigen relapse rates in patients with negative versus positive repeat biopsies. CONCLUSIONS: Our findings suggest that this 23% incidence of false-negative biopsies represents significant cancer. This relatively high incidence is important to consider in treatment modalities in which prostate biopsy may be performed to determine response to therapy.


Assuntos
Biópsia por Agulha/normas , Neoplasias da Próstata/patologia , Biópsia por Agulha/métodos , Reações Falso-Negativas , Humanos , Masculino , Estudos Prospectivos
4.
J Urol ; 158(6): 2113-7, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9366325

RESUMO

PURPOSE: We evaluated the morbidity and outcome of cystectomy and urinary diversion in patients 80 years old or older with invasive bladder cancer. MATERIALS AND METHODS: We reviewed the records of all patients older than 80 years who underwent cystectomy during the last 15 years. Of 1,186 cystectomies 44 patients (4%) were identified. Patients were evaluated for complications, mortality and functional status after surgery. RESULTS: The 44 patients had a median age of 81 years (range 80 to 87). Of the patients 78% had significant co-morbidity, including 41% with 2 or more medical problems. Median hospital stay was 14 days, with 20% of the patients requiring intensive care for 24 hours. There was a 51% complication rate including 25% due to surgical complications and 26% from underlying medical illness. Operative mortality was 4.5%. Within 6 months of surgery 66% were rehospitalized for medical or surgical reasons. Median survival time was 25 months. Median performance status before and after surgery decreased slightly from 70 to 65. CONCLUSIONS: The results of this study support the use of cystectomy in octogenarians with invasive bladder cancer. Surgery can be accomplished with acceptable morbidity and mortality. Radical cystectomy in this population offers the best opportunity for sustained disease-free quality survival.


Assuntos
Cistectomia , Neoplasias da Bexiga Urinária/cirurgia , Derivação Urinária , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Complicações Pós-Operatórias/epidemiologia , Taxa de Sobrevida , Neoplasias da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/mortalidade
5.
J Urol ; 158(3 Pt 1): 768-71, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9258077

RESUMO

PURPOSE: The clinical impact of ureteral carcinoma in situ identified at the time of radical cystectomy for bladder cancer has been poorly studied. We discuss our experience with this clinical problem in the context of published reports. MATERIALS AND METHODS: A total of 31 patients with concomitant ureteral carcinoma in situ was retrospectively identified among 401 consecutive radical cystectomies. End points analyzed included positive urinary cytology, upper tract recurrence of carcinoma and cancer specific survival. RESULTS: Ureteral margins were positive in 21 patients and negative in 10. Among 30 patients in whom it was performed frozen section failed to detect carcinoma in situ in 5 (16.6%) and sequential ureteral resection did not result in a negative margin in 15 (50%). In 3 patients upper tract carcinoma recurred at the anastomosis (1) and renal pelvis/ureter (2) at a median of 51 months (mean 49, range 36 to 59) following cystectomy. Positive cytology and upper tract carcinoma recurrence were not significantly associated with ureteral margin status, clinical or pathological bladder tumor stage or prior bacillus Calmette Guerin treatment. Median followup was 22.9 months (mean 31.8, range 2.0 to 74.2), during which 7 of the 31 patients died of metastatic bladder cancer. CONCLUSIONS: Concomitant ureteral carcinoma in situ is uncommon, and is rarely associated with local morbidity. It appears to confer increased risk for upper tract carcinoma recurrence, irrespective of margin status. In our experience upper tract carcinoma recurrence is heralded by positive cytology and generally appears only with protracted followup. Prognosis appears to be determined by the bladder tumor. Given the lack of morbidity and mortality attributable to concomitant ureteral carcinoma in situ, and the limited ability of frozen section examination to assist in its extirpation, the value of intraoperative identification of concomitant ureteral carcinoma in situ is questionable and expectant management is advised.


Assuntos
Carcinoma in Situ/patologia , Carcinoma in Situ/cirurgia , Cistectomia , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/cirurgia , Neoplasias Ureterais/patologia , Neoplasias Ureterais/cirurgia , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Estudos Retrospectivos
6.
Urology ; 49(3A Suppl): 113-8, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9123730

RESUMO

OBJECTIVES: Six random systematic core biopsies (SRSCB) of the prostate is considered by many to represent the standard method of detecting prostate cancer. We sought to evaluate the sensitivity of the transrectal ultrasound (TRU)S-guided needle biopsies in 89 consecutive patients with a history of biopsy-proven prostate cancer. These patients underwent repeat biopsy prior to enrollment in an ongoing, randomized protocol. We also compared the clinical and pathological features of patients with SRSCB-documented prostate carcinoma and negative repeat-sextant biopsy. METHODS: Our study population consisted of 89 patients enrolled in our randomized, prospective study assessing the effect of androgen deprivation therapy in combination with radical prostatectomy for clinically localized prostate cancer. A comparison was made of the patients' rebiopsy results with initial biopsy. Patients having either a positive or negative rebiopsy were analyzed with respect to grade, T stage, prostate-specific antigen (PSA), PSA density (PSAD), organ-confined rate, and final surgical margin status. RESULTS: Repeat sextant biopsy was positive for prostate cancer in 71 (80%) patients and negative in 18 (20%) patients. There was no significant difference between patients with a negative or positive rebiopsy with respect to PSA or PSAD. There was a trend toward greater prostate volumes in the negative-rebiopsy group (P = 0.08) and lower clinical stage in the negative rebiopsy (P = 0.025) group. In patients with a negative repeat biopsy, the organ-confined (OC) rate was 77% (14/18 patients), as compared to the positive-rebiopsy group of 56% (40/71 patients) (P = 0.08). Similarly, the margin-positive rate in the negative-rebiopsy group was 17% (3/18 patients), as compared to the positive-rebiopsy group who had a margin-positive rate of 44% (31/71 patients) (P = 0.03). CONCLUSIONS: In patients with clinically localized disease, the sensitivity of SRSCB in detecting carcinoma is 80%. The results of this study highlight the potential sampling error of the SRSCB and the implication of a negative rebiopsy in patients with clinically significant prostate cancer.


Assuntos
Biópsia por Agulha/estatística & dados numéricos , Neoplasias da Próstata/patologia , Antagonistas de Androgênios/uso terapêutico , Humanos , Masculino , Estudos Prospectivos , Prostatectomia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/terapia , Viés de Seleção , Sensibilidade e Especificidade , Ultrassonografia
7.
Urology ; 49(3A Suppl): 46-55, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9123736

RESUMO

OBJECTIVES: The use of neoadjuvant chemotherapy prior to definitive surgery has been firmly established in other areas of oncology, most notably in the treatment to testis and Wilm's tumors. The use of neoadjuvant androgen deprivation therapy (ADT) in conjunction with radical prostatectomy remains a source of controversy. We have conducted phase II and phase III studies to assess the effects of 3 months of preoperative ADT (goserelin and flutamide) on the pathologic staging and postsurgery prostate-specific antigen (PSA) relapse rate. We also reviewed the data confirming the understaging of clinically localized prostatic cancer and the experimental data providing the conceptual support for ADT. METHODS: We report the results of 141 patients, Stage T0-T0, in a Phase II study with concurrent, nonrandomized controls (N = 72) versus a treatment arm (N = 69) of men receiving 3 months of ADT with 3.6 mg goserelin for 28 days and 750 mg flutamide daily. We also report the interim results in 114 men participating in a prospective, randomized study of ADT versus surgery alone. RESULTS: The 69 patients who received 3 months of goserelin and flutamide followed by radical prostatectomy had a pathologic organ-confined cancer rate of 74%, versus 48% in the control group who received no ADT prior to surgery. The margin-positive rate was 10% in the ADT group versus 33% in the control group. In an interim analysis of 114 patients (59 ADT, 55 control), the organ-confined and margin-positive rates were 73% and 17% in the ADT group versus 56% and 36% in the control arm, respectively. The PSA disease-free rate at a mean follow-up of 28.6 months (range 6.2 to 49.5 months) was 89% in the ADT-treated patients (N = 98) and 84% in the control patients (N = 96). There was no statistical difference demonstrated between the arms with respect to biochemical failure. CONCLUSIONS: While the pathologic staging of tumors following ADT treatment was improved compared with surgical controls, to date the PSA disease-free survival rates are similar. Patients with residual extracapsular (P3) disease after ADT manifest an increased PSA failure rate compared with those with P3 tumors treated by surgery alone. This suggests that ADT may identify a subset of patients with aggressive tumors that may be candidates for additional therapeutic interventions even before PSA failure occurs.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Flutamida/uso terapêutico , Gosserrelina/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/cirurgia , Idoso , Quimioterapia Adjuvante , Quimioterapia Combinada , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Células Neoplásicas Circulantes/efeitos dos fármacos , Cuidados Pré-Operatórios , Neoplasias da Próstata/patologia
8.
Urology ; 49(3A Suppl): 95-101, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9123743

RESUMO

OBJECTIVE: An on-going study at the Memorial Sloan-Kettering Cancer Center assessed the effectiveness of androgen deprivation therapy (ADT) prior to surgical removal of the prostate. In this report, we evaluate the effectiveness of ADT on systemic disease by monitoring the presence or absence of circulating prostatic epithelial cells using a reverse transcription polymerase chain reaction (RT-PCR) assay for prostatic-specific membrane antigen (PSM). METHODS: PSM RT-PCR was performed on a total of 38 prostate cancer patients. There were 12 pT2 patients in the ADT group and 10 patients in the control pT2 group and 5 pT3 patients in the ADT group and 11 pT3 patients in the control group. RESULTS: For pT2 patients, 2 of the 12 patients (17%) were positive for circulating prostatic cells during androgen deprivation therapy but before radical retroprostatectomy (RRP). Within a 6-month period after RRP, 3 of 12 patients (25%) were positive. For the period between the 7th and 12th month after RRP, 6 of 12 patients (50%) were positive. For the period 12-36 months after RRP, 2 of the 12 patients (17%) remained positive for circulating prostatic cells. In contrast, the pT2 control group had higher positive rates in comparable periods: 4 of 10 patients (40%) were positive prior to surgery; 6 of 10 patients (60%) were positive during the 6 months following surgery. For the period between the 7th and 12th month following surgery, 4 of 7 patients (57%) were positive for PSM. Finally, 3 of 6 patients (50%) were positive for the period longer than 12 months. Regarding patients who have extraprostatic disease (stage pT3), the ADT group had a lower rate of circulating PSM positive cells. Before RRP and during androgen deprivation therapy, 1 out of 5 patients (20%) in the ADT group were positive as compared to 4 out of 11 patients for the control group. Within a 6-month period after RRP, the ADT group had 4 out of 9 (44%) patients positive for PSM as compared to 9 of 11 (82%) for the control group. For the period between the 7th and 12th months postsurgery, 1 of 5 patients (20%) of the ADT group were positive as compared to 4 of 7 (57%) of the control patients. CONCLUSIONS: These results indicate that patients with pT2 and pT3 lesions who receive neoadjuvant ADT are less likely to have circulating tumor cells detected compared to a control group both prior to and after surgery. In addition, irrespective of ADT or control group, there were increases in the detection of circulating tumor cells in the period after RRP, and this rise gradually decreased, suggesting that surgical manipulation may cause hematogenous dissemination of tumor cells and that ADT reduces such dissemination of tumor cells. Overall, these results indicate that the use of neoadjuvant ADT decreases the number of circulating prostatic cells. These data represent the initial results of an on-going study. As additional patients are added to the studies, attempts to correlate PSM positivity and serum PSA values postoperatively, recurrence, and margin positivity will be made.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Antígenos de Neoplasias/análise , Antígenos de Superfície/análise , Células Neoplásicas Circulantes/química , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Quimioterapia Adjuvante , Glutamato Carboxipeptidase II , Humanos , Masculino , Reação em Cadeia da Polimerase , Cuidados Pré-Operatórios , Neoplasias da Próstata/sangue
9.
Mol Cell Biol ; 16(1): 192-201, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8524296

RESUMO

NF-X1 is a novel cytokine-inducible transcription factor that has been implicated in the control of immune responses in humans, presumably by regulating expression of class II major histocompatibility genes. Here we report the cloning and genetic characterization of the first reported NF-X1 homolog, which is encoded by the Drosophila melanogaster shuttle craft (stc) gene. The deduced sequence of the fly and human proteins defines a new family of molecules distinguished by a novel cysteine-rich DNA-binding motif (consisting of seven copies of the consensus sequence Cx3Cx3LxCGx0-5HxCx3CHxGxCx2Cx7-9CxC). We have identified and begun a phenotypic characterization of mutations in the stc gene. stc mutants die at the end of embryogenesis, when they appear to be incapable of coordinating the typical peristaltic contraction waves normally required for embryos to hatch into feeding first instar larvae. Preliminary evidence indicates that the resulting lethality of this behavioral defect is accompanied by subtle morphological abnormalities in the central nervous system, where in wild-type embryos, STC protein is normally localized in the nuclei of repeated cell clusters within each neuromere and brain lobe. Thus, the NF-X1 homolog encoded by the Drosophila stc gene defines a new family of putative transcription factors and plays an essential role in the completion of embryonic development. This study presents the first in vivo genetic analysis of a member of this new protein family.


Assuntos
Proteínas de Ligação a DNA/genética , Drosophila melanogaster/genética , Genes de Insetos , Fatores de Transcrição/genética , Alelos , Sequência de Aminoácidos , Animais , Sequência de Bases , Sistema Nervoso Central/embriologia , Mapeamento Cromossômico , Clonagem Molecular , Primers do DNA/genética , DNA Complementar/genética , Drosophila melanogaster/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Dados de Sequência Molecular , Fatores de Transcrição de Fator Regulador X , Sequências Repetitivas de Ácido Nucleico , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
11.
Biochim Biophys Acta ; 1218(2): 245-9, 1994 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-8018733

RESUMO

Eukaryotic high mobility group (HMG) proteins such as Drosophila melanogaster HMG D, are thought to be nonhistone components of chromatin. However, we have observed an unusual sequestering of HMG D maternal mRNA within the periphery of oocytes during late oogenesis and zygotic expression confined to the developing embryonic nervous system. Hence, rather than being ubiquitously expressed, HMG D transcripts display a complex pattern of temporal and spatial localization implying a specialized rather than general role during early fly development.


Assuntos
Drosophila melanogaster/genética , Proteínas de Grupo de Alta Mobilidade/genética , Zigoto/metabolismo , Animais , Drosophila melanogaster/embriologia , Feminino , RNA Mensageiro/análise
12.
Gene ; 143(2): 171-7, 1994 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-8206370

RESUMO

Little is known about the identity and involvement of single-stranded (ss) DNA-binding (SSB) and RNA-binding proteins in developmental processes that occur during oogenesis in Drosophila melanogaster (Dm). Here, we describe a molecular approach designed to identify such proteins by virtue of their ssDNA-binding activity. We have constructed a directional ovarian cDNA library and conducted expression cloning screens which identified five unique cDNAs that encode proteins capable of binding ssDNA. All five represent previously unreported sequences. The remainder of this paper focuses on one of these cDNAs which encodes a Dm protein displaying significant sequence homology to Escherichia coli ssDNA-binding protein (SSB, involved in DNA replication, repair and recombination), as well as eukaryotic SSBs isolated from the mitochondria (mt) of rats, frogs, humans and yeast. The deduced amino acid (aa) sequence of this 15.6-kDa protein, which we will refer to as Dm mtSSB, displays average identities of 38.3% with eukaryotic mtSSBs and 23.4% with bacterial SSBs. Gel retardation analysis with an affinity-purified GST fusion protein confirms that Dm mtSSB specifically binds ss, but not double stranded DNA. Dm mtSSB is encoded by a nuclear gene whose expression appears to be developmentally regulated. It is expressed as a single 600-nucleotide (nt) transcript during oogenesis and embryogenesis. A larger transcript of 1500 nt is prevalent in some later stages of Dm development.


Assuntos
Proteínas de Ligação a DNA/biossíntese , Proteínas de Drosophila/biossíntese , Drosophila melanogaster/metabolismo , Proteínas de Ligação a RNA/biossíntese , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/química , Sequência de Bases , DNA Complementar/química , DNA de Cadeia Simples/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Drosophila/química , Drosophila melanogaster/citologia , Feminino , Mitocôndrias/química , Dados de Sequência Molecular , Oogênese/fisiologia , Ovário/química , Proteínas de Ligação a RNA/química , Homologia de Sequência de Aminoácidos
13.
Mol Cell Biol ; 13(9): 5898-906, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8355717

RESUMO

An 84-bp proximal regulatory protein (PRR) of the Drosophila melanogaster s36 chorion gene is sufficient for directing proper temporal and spatial expression of a reporter gene in three domains of the follicle: anterior, posterior, and main body. Here we show that the fidelity of PRR-directed s36 expression is dependent on the proper dorsal-ventral differentiation of the follicular epithelium, which requires the Drosophila epidermal growth factor receptor homolog. Transgenic analysis of site-directed mutants of the PRR suggests that s36 expression is regulated by the concerted action of multiple positive activators. Several cis-acting transcriptional elements have been identified: some appear to function in a quantitative manner, while others either are essential or appear to regulate expression in particular spatial domains. The approximate locations of these regulatory elements have been defined; some map within sequences that are strongly conserved in widely divergent dipteran species. In fact, the PRR analog of the medfly Ceratitis capitata Ccs36 gene directs expression in a manner similar to the D. melanogaster s36 PRR. We propose a model for transcriptional regulation of s36 based on the prechoriogenic polarization of the follicular epithelium that surrounds the developing egg chamber.


Assuntos
Córion , Drosophila melanogaster/genética , Proteínas do Ovo/genética , Regulação da Expressão Gênica , Genes de Insetos , Oogênese , Sequências Reguladoras de Ácido Nucleico , Animais , Sequência de Bases , Drosophila melanogaster/embriologia , Feminino , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Ovário/metabolismo
14.
Urology ; 41(6): 568-70, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8516995

RESUMO

We report on an eighty-year-old Haitian man with a suprapubic mass of seven months duration after five years of urinary diversion for urethral stricture. Histologically the mass was a squamous cell carcinoma confined to the suprapubic tract without bladder involvement. We believe this is the first such case reported in the literature, and it stresses the need for close monitoring of patients with any type of long-term indwelling catheter.


Assuntos
Carcinoma de Células Escamosas/etiologia , Bexiga Urinária/cirurgia , Derivação Urinária/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Humanos , Masculino , Osso Púbico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...